This update includes upgraded AV1 (*.avif) support (both opening and saving, and not just on Win10) thanks to the bundling of @null54‘s AvifFileType plugin. Performance and memory usage are improved, particularly when working with large images. Saving large, indexed (8-bit or less) image has been fixed, as well as the palette generation for 4-bit images (which was broken).
To get this update, make sure you have "Also check for pre-release (beta) versions" enabled in Settings, and then click on the Check Now button. (Unfortunately alpha/beta releases are not currently available for the Microsoft Store version of the app).
You can also download and install this update directly from the forum.
Changes since 4.2.13:
- New: AV1 (*.avif) images can now be saved (not just opened), due to bundling of @null54‘s AvifFileType plugin (v1.0.4.0). Installation of Microsoft’s codec from the Microsoft Store is no longer necessary, which means this also works on Windows 7 and 8.1.
- Improved performance in the canvas rendering engine, especially when working with large images, and most notably when scrolling and zooming
- Reduced memory usage when working with images that have regions of solid color
- Fixed an issue where saving an image at 4-bit color depth (usually pixel art) was using an incorrect palette (reduced color count/quality). This was due to a bug in Windows Imaging Component (WIC).
- Fixed an issue where very large images (e.g. 50000 x 50000 px) couldn’t be saved at indexed bit-depths (8-bit or less) due to a bug in Windows Imaging Component (WIC). More information on the forum: https://forums.getpaint.net/topic/116950-error-when-saving-a-big-file/
- Fixed an issue where BMP images couldn’t be loaded if they had the .PNG extension (there’s an Android screenshot utility out there which does this …)
- Fixed a rare crash in the Gradient tool ("The tool must be in the Drawing state …")
- New: Added a list of the DLLs that are loaded into the process on the Settings → Diagnostics page. This is to help troubleshooting scenarios.
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Cannot update. Repeatedly getting “There was an error decompressing the download.”
What version of the app are you currently using? And, which version of Windows?
Did you find a workaround for the WIC bug or did Microsoft fix the bug?
(If they fixed the bug I guess it would apply to older PDN versions too)
I implemented workarounds.
For the palette generation bug, whereby WIC can’t handle generating a palette for a large image (larger than about 2.6 GB of pixel data), I ask WIC to generate a palette from scaled-down version of the image. I use nearest neighbor sampling to ensure colors don’t get changed, although this does introduce the problem that some colors may be missed. Especially if there is a very regular grid/stipple pattern in the image.
There are actually 2 bugs in WIC’s code path here that I had to dodge. The first is an arithmetic overflow that it catches and returns as a failure HRESULT (translated to a managed exception). The other is actually a divide by zero! It comes as an SEH exception, WIC doesn’t handle it, and it results in a memory leak. So I have to resize the image to less than about 1.7 GB to dodge this.
Interesting, thanks for the information!
So if Microsoft somehow fixes the issue on their end, will that interfere with the PDN workaround?
It shouldn’t interfere. If they fix the bugs, PDN won’t have to use its alternate code path.
Saving AVIF at 100% quality produces corrupted colours, any lower quality works normally. Other settings don’t matter. Loading corrupted image in paint.net makes it look normal again but other decoders show it with corrupted colours.
Thanks for reporting this — I’ve filed an issue on GitHub that you can watch: https://github.com/0xC0000054/pdn-avif/issues/10